TY - JOUR

T1 - NADH-Free Electroenzymatic Reduction of CO2 by Conductive Hydrogel-Conjugated Formate Dehydrogenase

AU - Kuk, Su Keun

AU - Gopinath, Krishnasamy

AU - Singh, Raushan K.

AU - Kim, Tae Doo

AU - Lee, Youngjun

AU - Choi, Woo Seok

AU - Lee, Jung Kul

AU - Park, Chan Beum

PY - 2019

Y1 - 2019

N2 - The electrocatalytic reduction of CO2 under low overpotential and mild conditions using redox enzyme is a propitious route for carbon capture and conversion. Here, we report bioelectrocatalytic CO2 conversion to formate by conjugating a strongly CO2-reductive, W-containing formate dehydrogenase from Clostridium ljungdahlii (ClFDH) to conductive polyaniline (PANi) hydrogel. The ClFDH in the hybrid electrode successfully gained electrons directly from PANi and exhibited high capability for electroenzymatic conversion of CO2 to formate at low overpotential without NADH. We describe a potential electron-transfer pathway in the PANi-ClFDH bioelectrode on the basis of multiple spectroscopic analyses and a QM/MM-based computational study. The 3D-nanostructured PANi hydrogel facilitated rapid electron injection to the active site of ClFDH. In the absence of NADH, the PANi-ClFDH electrode showed stable CO2-to-formate transformation at an overpotential as low as 40 mV, with 1.42 μmol h-1 cm-2 conversion rate, 92.7% faradaic efficiency, and 976 h-1 turnover frequency.

AB - The electrocatalytic reduction of CO2 under low overpotential and mild conditions using redox enzyme is a propitious route for carbon capture and conversion. Here, we report bioelectrocatalytic CO2 conversion to formate by conjugating a strongly CO2-reductive, W-containing formate dehydrogenase from Clostridium ljungdahlii (ClFDH) to conductive polyaniline (PANi) hydrogel. The ClFDH in the hybrid electrode successfully gained electrons directly from PANi and exhibited high capability for electroenzymatic conversion of CO2 to formate at low overpotential without NADH. We describe a potential electron-transfer pathway in the PANi-ClFDH bioelectrode on the basis of multiple spectroscopic analyses and a QM/MM-based computational study. The 3D-nanostructured PANi hydrogel facilitated rapid electron injection to the active site of ClFDH. In the absence of NADH, the PANi-ClFDH electrode showed stable CO2-to-formate transformation at an overpotential as low as 40 mV, with 1.42 μmol h-1 cm-2 conversion rate, 92.7% faradaic efficiency, and 976 h-1 turnover frequency.

KW - bioelectrode

KW - CO reduction

KW - electrocatalysis

KW - formate dehydrogenase

KW - NADH-free biocatalysis

U2 - 10.1021/acscatal.9b00127

DO - 10.1021/acscatal.9b00127

M3 - Journal article

AN - SCOPUS:85067099167

VL - 9

SP - 5584

EP - 5589

JO - ACS Catalysis

JF - ACS Catalysis

SN - 2155-5435

IS - 6

ER -